如何使用UIWebView从Documents目录加载已保存的PDF？ - iOS Swift

Question

我正在创建UIImage生成的PDF并将其保存到设备中。我也在Core Data中保存该文件的路径。我可以检索路径并检查文件是否存在，但是当我尝试在UIWebView中加载PDF时，屏幕返回空白。我已经尝试加载请求以及加载数据，但没有一个接近的工作。我将此代码应用于TableView didSelectRow函数，因此当用户单击该单元格时，会出现一个可重用的弹出窗口，该弹出窗口将加载PDF。以下是我的代码。

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

    let selectedDoc = tableView.cellForRow(at: indexPath) as! DisplayMainSavedDataCell

    let document : String = selectedDoc.documentNameLabel.text!

    print(document)

    let path = fetchDocumentURL(documentName: document)

    let urlDoc = URL(fileURLWithPath: path)

    print(urlDoc)

    let request = URLRequest.init(url: urlDoc)

    let sb = UIStoryboard.init(name: "Main", bundle: nil)

    let popup = sb.instantiateViewController(withIdentifier: "pdfPopUp") as! PDFViewController

    popup.webView?.loadRequest(request)

    present(popup, animated: true)

}



func fetchDocumentURL (documentName: String) -> String {

    let docName = documentName

    let fetchRequest : NSFetchRequest<Document> = Document.fetchRequest()

    let predicate = NSPredicate(format: "docName == %@", docName as CVarArg)

    fetchRequest.predicate = predicate

    do {

        let results = try PersistenceService.context.fetch(fetchRequest)

        for result in results as [Document] {

            let path = result.docPath

            return path!

        }

        } catch{

            print("files does not exists or file missing")

            let path = "No path exists"

            return path

    }

    let path = "No path exists"

    return path

}